Here you go Carpediem--

.3675 I.D. after firing prior to any sizing
.3575 I.D. after sizing with expander ball removed
.3620 I.D. after sizing with expander ball installed

As stated in previous post my expander ball is .3635 so there is .0015" of spring back as the neck passes over the expander ball.

For your reference the neck thickness of the test case used above is .011". The thicker the neck the smaller will be the neck I.D. after resizing with the expander ball removed. Normally we don't resize w/o an expander ball in place so we would never know that there is a significant step down in neck diameter before pulling it over the expander ball in the normal FL resize with decapping and neck expansion operation.

For example: If your brass's neck diameter was .013" and went through my size die with the expander ball removed the I.D. coming out would be .004" smaller than my case or .3535.

I think all these dimensions are fine and have never had a split neck nor do I get inordinate case elongation. I believe the best indicator of overworking the metal of the case neck is splitting and considerable elongation. Both of these conditions can be exaggerated by poor neck lubrication.

Hope this is helpful.
Dennis